1. www.consorzio-cometa.it FESR Consorzio COMETA Grid Introduction and gLite Overview Corso di formazione sul Calcolo Parallelo ad Alte Prestazioni (edizione 2008) Annamaria Muoio– INFN Catania Catania, 04-06 Ottobre 2008

2. Corso di formazione sul Calcolo Parallelo ad Alte Prestazioni (edizione 2008) - CATANIA 2  Introduction  Grid Access  Security Services  Information & Monitoring Services  Job Management Services  Data Services Outline

3. Corso di formazione sul Calcolo Parallelo ad Alte Prestazioni (edizione 2008) - CATANIA Grid Aim ?  Grid Systems & Applications aim is to:  Integrate  Virtualise  Manage  RESOURCEs and SERVICEs across different VOs.  VO – Individuals and/or Institutions having direct access to resources.

4. Corso di formazione sul Calcolo Parallelo ad Alte Prestazioni (edizione 2008) - CATANIA Grid Requirements ?  Heterogeneous (OSes, Devs, Apps.)  VO Resource Sharing (Management, Security and Accounting)  Resource Utilisation (Reservation, Monitoring and Logging)  Job Execution (VO access, QoS, LCM, WFM, SLA)  Data Services (Integration, Provisioning, Cataloguing)  Security (Authentication, Authorisation)  Scalability  Availability (Disaster Recovery, Fault Management)

5. Corso di formazione sul Calcolo Parallelo ad Alte Prestazioni (edizione 2008) - CATANIA  Many VOs need sharing of resources through services  Accessing  Allocating  Monitoring  Job & Data Management  http://www.glite.org http://www.glite.org  Grid Middleware - Layer between services and resources  gLite - Lightweight Middleware for Grid Computing

6. Corso di formazione sul Calcolo Parallelo ad Alte Prestazioni (edizione 2008) - CATANIA gLite – Services 5 High level services + CLI & API Legend: Available Soon Available Job repository

7. Corso di formazione sul Calcolo Parallelo ad Alte Prestazioni (edizione 2008) - CATANIA Security Service Job Management Monitoring and Discovery Data Management High-level Applications and Tools

8. Corso di formazione sul Calcolo Parallelo ad Alte Prestazioni (edizione 2008) - CATANIA

9.  Identify entities (users, systems and services) when establishing a context for message exchange (Who are you?).  Aim - Provide a Credential having a universal value that works for many purposes across many infrastructures, communities, VOs and projects.  gLite uses:  PKI (X.509) infrastructure using CAs as thrusted third parties.   To reduce vulnerability, on the Grid user identification is done by using (short lived) proxies of their certificates  Certificates can  Be revocated  Be renewed (in case they are about to expire) Authentication

10. Corso di formazione sul Calcolo Parallelo ad Alte Prestazioni (edizione 2008) - CATANIA Information services are vital low level component of Grids.

11. Corso di formazione sul Calcolo Parallelo ad Alte Prestazioni (edizione 2008) - CATANIA  Provide information about Grid resources and their status.  This information is essential for the operation of the whole Grid, as it is via IS that the resources are discovered.  The published information is also used for monitoring and accounting purposes.  The approache: -Berkeley DB Information Index (BDII)

12. Corso di formazione sul Calcolo Parallelo ad Alte Prestazioni (edizione 2008) - CATANIA  The information hierarchically stored GRISStores information at resource level GIISStores information at site level BDIIStores information at VO level VO Level Site Level Resource Level User Application WMS Monitoring Services

13. Corso di formazione sul Calcolo Parallelo ad Alte Prestazioni (edizione 2008) - CATANIA

14.  Accumulates information about the resource usage done by users or groups of users (VOs).  Information on Grid Services/Resources needs sensors (Resource Metering, Metering Abstraction Layer, Usage Records).  Records are collected by the Accounting System (Queries: Users, Groups, Resource)  Grid services should register themselves with a pricing service when accounting for billing purposes. Accounting

15. Corso di formazione sul Calcolo Parallelo ad Alte Prestazioni (edizione 2008) - CATANIA  WMS set of middleware components responsible of distribution and management of jobs across Grid resources.  Two core components of WMS:  WM: accepts and satisfy requests for job management. Matchmaking is the process of assigning the best available resource.  Logging & Bookeeping : keeps track of job execution in term of events: (Submitted, Running, Done,...) Workload Management

16. Corso di formazione sul Calcolo Parallelo ad Alte Prestazioni (edizione 2008) - CATANIA  Service that represents the computing resource that is responsible of the job management: (submission, control, etc.)  The CE may be used by a Generic Client: an end-user interacting directly with the Computing Element, or the Workload Manager, which submits a given job to an appropriate CE found by a matchmaking process.  Two job submission models (accordingly to user requests and site policies):  PUSH(Eager Scheduling) (jobs pushed to CE),  PULL(Lazy Scheduling) (jobs coming from WMS when CE has free slots)  CE responsible to collect accounting information.

17. Corso di formazione sul Calcolo Parallelo ad Alte Prestazioni (edizione 2008) - CATANIA

18.  OS like file access metaphor.  LFN (Logical file name)  GUID (Grid unique identifier)  SimLinks  SURL (Site URL)  TURL (Transfer URL) Catalogs

19. Corso di formazione sul Calcolo Parallelo ad Alte Prestazioni (edizione 2008) - CATANIA  Data Scheduler (DS) Keeps track of user/service transfer requests  File Transfer/Placement Service (FTS/FPS)  Transfer Queue (Table)  Transfer Agent (Network) Data Movement

20. Corso di formazione sul Calcolo Parallelo ad Alte Prestazioni (edizione 2008) - CATANIA